If you look in the file system under \\Messiah\pc\interfce\Menu\new, you'll find that the menus are apparently implemented as a series of .tga images. And that's not even the weirdest thing. The game apparently doesn't even layer the graphics, because for each menu option, there is a complete image of the entire menu with that option selected. From a programming standpoint, it's an incredibly simplistic and unelegant approach (this is my opinion, not objective truth), and I've never seen it used anywhere else. But it does mean that the menu is defined in one resolution only. If it were to be bigger at higher resolutions, the image would need to be stretched, but it appears that this doesn't happen.